This invention relates in general to networks and more specifically to transfer of state information using network communications.
Networks are employed in various demanding applications including wireless communications and Voice Over Internet Protocol (VOIP) telephony. Such applications often require maintenance of status information pertaining to a particular communication session. Status information may include user billing information, call state information, network device status, and so on.
Maintenance of status information is particularly important in large network applications employing specific protocols to control message flow through the network. For example, in VOIP Internet telephony applications employing Session Initiation Protocol (SIP), users may initiate phone calls to other users. Different network devices, such as proxy servers, redirect servers, and registrars, facilitate establishing calls between one or more parties. Conventionally, each network device maintains local state information for each call or associated message-initiation sequence. Unfortunately, storage of such information at each device may require excess upkeep and memory. Storage of status information at a device can be inefficient when the device is no longer used for a call, such as when a call has been dropped, when a device malfunctions or becomes unavailable, etc.